U.S. patent number 5,749,028 [Application Number 08/672,344] was granted by the patent office on 1998-05-05 for multi-size photoreceptor flange bearing.
This patent grant is currently assigned to Xerox Corporation. Invention is credited to Dhirendra C. Damji, Richard W. Herzog.
United States Patent |
5,749,028 |
Damji , et al. |
May 5, 1998 |
Multi-size photoreceptor flange bearing
Abstract
A bearing for supporting a member in an electrophotographic
printing machine of the type having a latent image recorded in a
photoconductive drum and for alternatively receiving at least a
first shaft and a second shaft is provided. The first shaft has a
shape substantially physically different from the second shaft. The
bearing includes a body operably associated with the member, a
first feature operably associated with the body for supporting the
first shaft, and a second feature operably associated with the body
for supporting the second shaft, whereby the bearing may
accommodate both of the two shafts.
Inventors: |
Damji; Dhirendra C. (Webster,
NY), Herzog; Richard W. (Webster, NY) |
Assignee: |
Xerox Corporation (Stamford,
CT)
|
Family
ID: |
24698150 |
Appl.
No.: |
08/672,344 |
Filed: |
June 26, 1996 |
Current U.S.
Class: |
399/117;
492/18 |
Current CPC
Class: |
F16C
17/24 (20130101); G03G 15/751 (20130101); G03G
2221/183 (20130101) |
Current International
Class: |
F16C
17/00 (20060101); F16C 17/24 (20060101); G03G
15/00 (20060101); G03G 021/00 () |
Field of
Search: |
;399/117,116,411
;492/18,47 |
References Cited
[Referenced By]
U.S. Patent Documents
Primary Examiner: Moses; R. L.
Attorney, Agent or Firm: Wagley; John S.
Claims
We claim:
1. A bearing for supporting a member in an electrophotographic
printing machine of the type having a latent image recorded in a
photoconductive drum and for alternatively receiving at least a
first shaft and a second shaft, the first shaft having a shape
substantially physically different from the second shaft, said
bearing comprising:
a body operably associated with the member;
a first feature operably associated with said body for supporting
the first shaft; and
a second feature operably associated with said body for supporting
the second shaft, whereby the bearing may accommodate both of the
two shafts.
2. The bearing of claim 1, wherein:
the second shaft has a cylindrical base and a cylindrical stem
extending concentrically therefrom; and
said body defining a aperture therein, the aperture including a
first bore matingly fittable to the stem and a second bore,
concentric to the first bore and matingly fittable to the base.
3. The bearing of claim 2, wherein the first bore is concentric
with the second bore within approximately 0.03 mm.
4. The bearing of claim 2, wherein the first bore is concentric
with an external periphery of said body within approximately 0.03
mm.
5. The bearing of claim 2, wherein the first bore has a length
along its rotational axis of approximately 30 to 70 percent of the
length of the second bore along its rotational axis.
6. The bearing of claim 1, wherein said body comprises a self
lubricating material.
7. The bearing of claim 1, wherein said self lubricating material
comprises sintered bronze.
8. The bearing of claim 1, wherein said body comprises an
electrically conductive material.
9. The bearing of claim 1, wherein said electrically conductive
material comprises carbon.
10. A customer replaceable unit including a processing station for
use in a printing machine, said customer replacement unit including
a bearing for supporting a moving member on a support structure and
for alternatively receiving at least a first shaft and a second
shaft, the bearing comprising:
a body operably associated with the member; and
a sleeve matingly fitted at least Partially within said body, said
sleeve including a first feature operably associated with said
sleeve for supporting the first shaft and a second feature operably
associated with said sleeve for supporting the second shaft,
whereby the bearing may accommodate both of the two shafts.
11. The customer replaceable unit of claim 10, wherein:
the second shaft has a cylindrical base and a cylindrical stem
extending concentrically therefrom; and
said sleeve defining a aperture therein, the aperture including a
first bore matingly fitable to the stem and a second bore,
concentric to the first bore and matingly fitable to the base.
12. The customer replaceable unit of claim 11, wherein the first
bore is concentric with the second bore within approximately 0.03
mm.
13. The customer replaceable unit of claim 11, wherein the first
bore is concentric with an external periphery of the sleeve within
approximately 0.03 mm.
14. The customer replaceable unit of claim 11, wherein the first
bore has a length along its rotational axis of approximately 30 to
70 percent of the length of the second bore along its rotational
axis.
15. The customer replaceable unit of claim 10, wherein said sleeve
comprises a self lubricating material.
16. The customer replaceable unit of claim 10, wherein said self
lubricating material comprises sintered bronze.
17. The customer replaceable unit of claim 10, wherein said sleeve
comprises an electrically conductive material.
18. The customer replaceable unit of claim 10, wherein said
electrically conductive material comprises carbon.
19. An electrophotographic printing machine of the type having a
latent image recorded in a photoconductive drum, said machine
including a bearing for supporting the drum and for alternatively
receiving at least a first shaft and a second shaft, the bearing
comprising:
a body operably associated with the member; and
a sleeve matingly fitted at least partially within said body, said
sleeve including a first feature operably associated with said
sleeve for supporting the first shaft and a second feature operably
associated with said sleeve for supporting the second shaft,
whereby the bearing may accommodate both of the two shafts.
20. The printing machine of claim 19, wherein:
the second shaft has a cylindrical base and a cylindrical stem
extending concentrically therefrom; and
said sleeve defining a aperture therein, the aperture including a
first bore matingly fitable to the stem and a second bore,
concentric to the first bore and matingly fitable to the base.
21. The printing machine of claim 20, wherein the first bore is
concentric with the second bore within approximately 0.03 mm.
22. The printing machine of claim 20, wherein the first bore is
concentric with an external periphery of the sleeve within
approximately 0.03 mm.
23. The printing machine of claim 20, wherein the first bore has a
length along its rotational axis of approximately 30 to 70 percent
of the length of the second bore along its rotational axis.
24. The printing machine of claim 19, wherein said sleeve comprises
a self lubricating material.
25. The printing machine of claim 19, wherein said self lubricating
material comprises sintered bronze.
26. The printing machine of claim 19, wherein said sleeve comprises
an electrically conductive material.
27. The printing machine of claim 19, wherein said electrically
conductive material comprises carbon.
Description
The present invention relates to photoconductive drums used in
electrophotographic printing machines. More particularly, the
invention relates to bearings for supporting the photoconductive
drum.
BACKGROUND OF THE INVENTION
A photoconductive member is a cylindrical or belt-like substrate
used in an electrophotographic printing machine. A substrate is
coated with one or more layers of a photoconductive material, i.e.,
a material whose electrical conductivity changes upon illumination.
The photoconductive member includes, for example, an aluminum
cylinder having a thin layer of a photoconductive organic compound
thereon. In electrophotographic printing, an electrical potential
is applied across the photoconductive layer and then exposed to
light of an image. The electrical potential of the photoconductive
layer decays at the portions irradiated by the light, leaving a
distribution of electrostatic charge corresponding to the dark
areas of the projected image. The electrostatic latent image is
made visible by development with a suitable powder.
Typically, the photoconductive surface of the photoconductive drum
has a surface life significantly less than that of the copier.
Typical life of a photoconductive surface of a photoconductive
member is approximately 20,000 copies. Thus, the photoconductive
drum is replaced several times during the life of the machine. The
photoconductive drum may either be an individual component that is
replaced in the machine or more commonly contained within a
housing, typically referred to as a CRU (customer replaceable
unit). The photoconductive member is enclosed within the CRU to
protect the photoconductive member from exposure to light and to
protect it from damage during assembly into the copier.
The photoconductive drum is required to rotate within the copier
and this is typically accomplished through a hub extending
outwardly from an end of the photoconductive drum. OEM (original
equipment manufacturers) often have various size shafts to which an
opening in the hub of the photoconductive drum is engaged to
provide the rotation. The shafts of the copiers typically have a
cylindrical configuration with a specified diameter and length. The
hub of the photoconductive drum therefore matingly fits with the
shaft of the copier.
For low volume copiers (those which make for example 15 cpm or
less) typically have photoconductive drums with one of a few
standard diameters and lengths. This is because the length of the
photoconductive drum determines the width of substrate that may be
printed (copy paper used), for example, an 81/2 by 11 inch sheet of
paper. To permit copy in both length and width orientations, the
photoconductive drum is thus slightly larger than 11 inches in
length. The diameter of the photoconductive drum is typically in
the order of one to two inches.
Many different photoconductive compositions may be utilized in
copiers. While some of the photoconductive compositions have
different physical characteristics, such as different colors, many
of the compositions are physically similar. Distinguishing the
respectively photoconductive drums is thus a major problem.
Segregating identical photoconductive drums within a manufacturing
facility represents one particular problem. A second problem is
assuring that the proper photoconductive drum is placed within a
machine when the photoconductive drum is replaced.
Further complications are involved in that OEM copier manufacturers
may each have their own particular drive shaft diameters even for
machines that utilize a photoconductive drum manufactured of the
same photoconductive material. Therefore, often different OEM
manufacturers will have their own individual photoconductive drums
which differ from each other only in the adaptors required for the
different drive shafts of the respective copiers. Manufacturers of
photoconductive drums typically manufacture the drums for several
different OEM manufacturers. Therefore, these photoconductive drum
manufacturers may produce small runs of a variety of different
photoconductive drums. This results in small runs of many different
photoconductive drums and respective large quantities of different
drums in inventory.
Furthermore, many different photoconductive drums differing only in
the photoconductive material may be hard to visually distinguish.
While some may be made of different colors, others have the same
color and are only distinguishable by a label attached thereto. The
use of the similar photoconductive drums creates segregation
problems within a manufacturing facility and quality and
reliability problems during servicing of the copiers with
uncertainty as to whether the photoreceptive drum has been replaced
with the proper drum. Typically, any one of several photoconductive
drums may be inserted into a copy machine needing servicing, while
only one of these photoconductive drums may provide proper quality
and service life to the customer.
This invention is intended to address at least some of the
aforementioned problems.
The following disclosures may be relevant to various aspects of the
present invention:
______________________________________ U.S. Pat. No. A-5,465,136
Patentee: Watanabe Issue Date: November 7, 1994 U.S. Pat. No.
A-5,357,321 Patentee: Stenzel et al. Issue Date: October 18, 1994
U.S. Pat. No. A-5,151,737 Patentee; Johnson et al Issue Date:
September 29, 1992 U.S. Pat. No. A-5,107,304 Patentee: Haneda et
al. Issue Date: April 21, 1992 U.S. Pat. No. A-4,996,566 Patentee:
Morita et al. Issue Date: February 26, 1991 U.S. Pat. No.
A-4,954,844 Patentee: Morita et al. Issue Date: September 4, 1990
U.S. Pat. No. A-4,941,018 Patentee: Kasamura et al. Issue Date:
July 10, 1990 U.S. Pat. No. A-4,878,091 Patentee: Morita et al.
Issue Date: October 31, 1989 U.S. Pat. No. A-4,621,919 Patentee:
Nitanda et al. Issue Date: November 11, 1986 U.S. Pat. No.
A-4,561,763 Patentee: Basch Issue Date: December 31, 1985 U.S. Pat.
No. A-4,400,077 Patentee: Kozuka et al. Issue Date: August 23, 1983
U.S. Pat. No. A-4,120,576 Patentee: Babish Issue Date: October 17,
1978 U.S. Pat. No. A-4,105,345 Patentee: Van Wagner Issue Date:
August 8, 1978 U.S. Pat. No. A-4,040,157 Patentee: Shanly Issue
Date: August 9, 1977 U.S. Pat. No. A-3,994,053 Patentee: Hunt Issue
Date: November 30, 1976 ______________________________________
The relevant portions of the foregoing disclosures may be briefly
summarized as follows:
U.S. Pat. No. 5,465,136 to Watanabe discloses a process cartridge
which is detachable from an image forming apparatus. The process
cartridge includes a charging roll that is in contact with a
photosensitive drum when the cartridge is operational. Pressure
releasing pieces separate the roll from the drum. Gripping members
contact the frame when the cartridge would be in contact with the
drum to prevent damage to the drum during installation.
U.S. Pat. No. 5,357,321 to Stenzel et al. discloses a drum
supporting hub including a disc shaped member having a circular
periphery. A hole extends axially through the center of the disc
shaped member and a long thin electrically conductive resilient
s-shaped member is trapped between flared edges and an axle shaft
and the ends of the s-shaped member contact the inner periphery of
the disc shaped member.
U.S. Pat. No. 5,151,737 to Johnson et al. discloses a hollow
cylindrical shell having an axial slit. Axial ribs extend inwardly
from the shell. Conical wedges are fitted to the ends of the shell
and the conical surface of the wedges contact chamfers on the ribs.
A shaft is slidably fitted to an axial opening in the wedges. A nut
on an end of the shaft is used to draw the wedges together causing
the shell to expand.
U.S. Pat. No. 5,107,304 to Haneda et al. discloses a multi-color
image forming apparatus having an plurality of developing devices.
Each of the developing devices are mounting in a specific position
in the apparatus. Fool proof mechanisms are taken to prevent the
developing device to be mounted in an improper location.
U.S. Pat. No. 4,996,566 to Morita et al. discloses a multi-color
image forming apparatus having an plurality of developing units.
Each of the developing devices are mounting in a specific position
in the apparatus. In case an operator makes a mistake when the
developing units are inserted into the apparatus, a fool proof
mechanism is used to prevent the developing device to be mounted in
an improper location.
U.S. Pat. No. 4,954,844 to Morita et al. discloses a multi-color
image forming apparatus having an plurality of developing units.
Each of the developing devices are mounting in a specific position
in the apparatus. In case an operator makes a mistake when the
developing units are inserted into the apparatus, a fool proofing
device is used. In such a device pins are provided on the front
faces of the in different vertical positions on the of the
developing units. The pins mate with grooves to prevent the
developing device to be mounted in an improper location.
U.S. Pat. No. 4,941,7018 to Kasamura et al. discloses an image
forming apparatus having a developing unit and a photosensitive
member. The developing unit is mounted slidably by a pair of
guiding passages. The driving passage nearer the photoresistive
member is narrower than the other passage to prevent the developer
unit to be incorrectly mounted.
U.S. Pat. No. 4,878,091 to Morita et al. discloses a multi-color
image forming apparatus having an plurality of developing units.
Each of the developing devices are mounting in a specific position
in the apparatus. In case an operator makes a mistake when the
developing units are inserted into the apparatus, pins are provided
on the front faces of the in different vertical positions on the of
the developing units. The pins mate with grooves to prevent the
developing device to be mounted in an improper location.
U.S. Pat. No. 4,621,919 to Nitanda et al. discloses a
photoreceptive drum having a face integrally formed on one side of
the drum. An integrally formed shaft extends from the integrally
formed face.
U.S. Pat. No. 4,561,763 to Basch discloses a cylindrical drum
assembly including a pair of drum supporting hubs positioned on the
ends of a cylindrical drum. The hubs include an annular ring having
resilient finger extending from the ring. An external recess on a
disc shaped end plate fits inside the fingers while the inner
periphery of the cylindrical drum fits outside the fingers. The
fingers connect the drum to the plate.
U.S. Pat. No. 4,400,077 to Kozuka et al. discloses a photosensitive
drum assembly having a cylindrical drum and two disc shaped flanges
positioned on the ends of the drum. The flanges each include a lip
which is closely fitted to the external periphery of the drum.
Connecting rods interconnect the flanges.
U.S. Pat. No. 4,120,576 to Babish discloses a drum support
apparatus for supporting a cylindrical drum. The apparatus includes
a pair of hubs each having a central stem. A shaft interconnects
the hubs and has a loosely fitted tube over the shaft. The
periphery of the stem fits with the inner periphery of the tube.
Tabs on the shaft interconnect with a slot in the stem.
U.S. Pat. No. 4,105,345 to Van Wagner discloses a drum support
assembly including a cylindrical drum having spaced apart internal
grooves and a pair of hubs. The hubs each have four equally spaced
radially sliding lock plates with an outer edge which matingly fits
into the grooves. A centrally located shaft is secured to the hubs
and interconnects them.
U.S. Pat. No. 4,040,157 to Shanly discloses a drum support assembly
a cylindrical hub and two conical shaped hubs. The hubs include
equally spaced lobes on the periphery of the hubs which mate with
an internal periphery on the ends of the hub. A shaft is fitted to
the center of the hubs and three equally spaced tie rods
interconnect the hubs.
U.S. Pat. No. 3,994,053 to Hunt discloses a drum support assembly a
cylindrical hub and two conical shaped hubs. The hubs include
equally spaced lobes on the periphery of the hubs which mate with
an internal periphery on the ends of the hub. A shaft is fitted to
the center of the hubs and three equally spaced tie rods
interconnect the hubs.
All of the references cited herein above are incorporated by
reference for their teachings.
SUMMARY OF THE INVENTION
In accordance with one aspect of the present invention, there is in
provided a bearing for supporting a member in an
electrophotographic printing machine of the type having a latent
image recorded in a photoconductive drum and for alternatively
receiving at least a first shaft and a second shaft. The first
shaft has a shape substantially physically different from the
second shaft. The bearing includes a body operably associated with
the member, a first feature operably associated with the body for
supporting the first shaft, and a second feature operably
associated with the body for supporting the second shaft, whereby
the bearing may accommodate both of the two shafts.
In accordance with another aspect of the present invention, there
is provided a customer replaceable unit including a processing
station for use in a printing machine. The customer replacement
unit includes a bearing for supporting a moving member on a support
structure and for alternatively receiving at least a first shaft
and a second shaft. The first shaft has a shape substantially
physically different from the second shaft. The bearing includes a
body operably associated with the member, a first feature operably
associated with the body for supporting the first shaft, and a
second feature operably associated with the body for supporting the
second shaft, whereby the bearing may accommodate both of the two
shafts.
In accordance with further aspect of the present invention, there
is provided an electrophotographic printing machine of the type
having a latent image recorded in a photoconductive drum. The
machine includes a bearing for supporting the drum and for
alternatively receiving at least a first shaft and a second shaft.
The bearing includes a body operably associated with the drum, a
first feature operably associated with the body for supporting the
first shaft, and a second feature operably associated with the body
for supporting the second shaft, whereby the bearing may
accommodate both of the two shafts.
These and other aspects of the invention will become apparent from
the following descriptions to illustrate a preferred embodiment of
the invention read in conjunction with the accompanying
drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
The invention will be described in detail herein with reference to
the following figures in which like reference numerals denote like
elements and wherein:
FIG. 1A is a partial plan view of a photoreceptor drum in a CRU
including a multi-size photoreceptor flange bearing according to
the present invention;
FIG. 1B is a partial plan view of a multi-step shaft for engagement
with the multi-size photoreceptor flange bearing of FIG. 1;
FIG. 2 is a schematic elevational view of an illustrative
electrophotographic printing machine incorporating the bearing of
the present invention therein;
FIG. 3 is a partial plan view of a multi-step shaft in engagement
with the multi-size photoreceptor flange bearing of FIG. 1;
FIG. 4 is a partial plan view of the CRU of FIG. 1A unsuccessfully
attempted to be installed in an improper copy machine;
FIG. 5 is a partial plan view of a CRU incorporating the multi-size
photoreceptor flange bearing according to the present invention
with an alternate second hub support configuration;
FIG. 6A is a partial plan view of a square shaft for engagement
with a multi-size photoreceptor flange bearing according to the
present invention;
FIG. 6B is a partial end view of the square shaft of FIG. 6A;
FIG. 6C is a partial plan view of a triangular shaft for engagement
with a multi-size photoreceptor flange bearing according to the
present invention;
FIG. 6D is a partial end view of the triangular shaft of FIG.
6C;
FIG. 6E is a partial plan view of a pentagon shaft for engagement
with a multi-size photoreceptor flange bearing according to the
present invention;
FIG. 6F is a partial end view of the triangular shaft of FIG.
6E;
FIG. 6G is a partial plan view of a hexagonal shaft for engagement
with a multi-size photoreceptor flange bearing according to the
present invention; and
FIG. 6H is a partial end view of the hexagonal shaft of FIG.
6G.
While the present invention will be described in connection with a
preferred embodiment thereof, it will be understood that it is not
intended to limit the invention to that embodiment. On the
contrary, it is intended to cover all alternatives, modifications,
and equivalents as may be included within the spirit and scope of
the invention as defined by the appended claims.
DETAILED DESCRIPTION OF THE INVENTION
Referring now to the drawings where the showings are for the
purpose of describing an embodiment of the invention and not for
limiting same, initially, the principle of the invention will be
discussed. While the present invention will be described in
connection with a preferred embodiment thereof, it will be
understood that it is not intended to limit the invention to that
embodiment. On the contrary, it is intended to cover all
alternatives, modifications, and equivalents as may be included
within the spirit and scope of the invention as defined by the
appended claims.
For a general understanding of the illustrative electrophotographic
printing machine incorporating the features of the present
invention therein, reference is made to the drawings. In the
drawings, like reference numerals have been used throughout to
designate identical elements. FIG. 6 schematically depicts the
various components of an electrophotographic printing machine
incorporating the corona discharge device of the present invention
therein. Although the corona discharge device of the present
invention is particularly well adapted for use in the illustrative
printing machine, it will become evident that these corona
discharge devices are equally well suited for use in a wide variety
of uses and are not necessarily limited in their application to the
particular embodiments shown herein.
Referring now to FIG. 6, the electrophotographic printing machine
shown employs a photoconductive drum 16, although photoreceptors in
the form of a belt are also known, and may be substituted therefor.
The drum 16 has a photoconductive surface deposited on a conductive
substrate. Drum 16 moves in the direction of arrow 18 to advance
successive portions thereof sequentially through the various
processing stations disposed about the path of movement thereof.
Motor 26 rotates drum 16 to advance drum 16 in the direction of
arrow 18. Drum 16 is coupled to motor 26, by suitable means such as
a drive.
Initially successive portions of drum 16 pass through charging
station A. At charging station A, a corona generating device,
indicated generally by the reference numeral 30, charges the drum
16 to a selectively high uniform electrical potential. The
electrical potential is normally opposite in sign to the charge of
the toner. Depending on the toner chemical composition, the
potential may be positive or negative. Any suitable control, well
known in the art, may be employed for controlling the corona
generating device 30.
A document 34 to be reproduced is placed on a platen 22, located at
imaging station B, where it is illuminated in a known manner by a
light source such as a lamp 24 with a photo spectral output
matching the photo spectral sensitivity of the photoconductor. The
document thus exposed is imaged onto the drum 16 by a system of
mirrors 26 and lens 27, as shown. The optical image selectively
discharges surface 28 of the drum 16 in an image configuration
whereby an electrostatic latent image 32 of the original document
is recorded on the drum 16 at the imaging station B.
At development station C, a development system or unit, indicated
generally by the reference numeral 36 advances developer materials
into contact with the electrostatic latent images. The developer
unit 36 includes a device to advance developer material into
contact with the latent image.
The developer unit 36, in the direction of movement of drum 16 as
indicated by arrow 18, develops the charged image areas of the
photoconductive surface 28. This developer unit contains black
developer, for example, material 44 having a triboelectric charge
such that the black toner is urged towards charged areas of the
latent image by the electrostatic field existing between the
photoconductive surface and the electrically biased developer rolls
in the developer unit which are connected to bias power supply
42.
A sheet of support material 58 is moved into contact with the toner
image at transfer station D. The sheet of support material 58 is
advanced to transfer station D by conventional sheet feeding
apparatus, not shown. Preferably, the sheet feeding apparatus
includes a feed roll contacting the uppermost sheet of a stack of
copy sheets. Feed rolls rotate so as to advance the uppermost sheet
from the stack into a chute which directs the advancing sheet of
support material into contact with the photoconductive surface of
drum 16 in a timed sequence so that the toner powder image
developed thereon contacts the advancing sheet of support material
at transfer station D.
Transfer station D includes a corona generating device 60 which
sprays ions of a suitable polarity onto the backside of sheet 58.
This attracts the toner powder image from the drum 16 to sheet 58.
After transfer, the sheet continues to move, in the direction of
arrow 62, onto a conveyor (not shown) which advances the sheet to
fusing station E.
Fusing station E includes a fuser assembly, indicated generally by
the reference numeral 64, which permanently affixes the transferred
powder image to sheet 58. Preferably, fuser assembly 64 comprises a
heated fuser roller 66 and a pressure roller 68. Sheet 58 passes
between fuser roller 66 and pressure roller 68 with the toner
powder image contacting fuser roller 66. In this manner, the toner
powder image is permanently affixed to sheet 58. After fusing, a
chute, not shown, guides the advancing sheet 58 to a catch tray,
also not shown, for subsequent removal from the printing machine by
the operator. It will also be understood that other post-fusing
operations can be included, for example, binding, inverting and
returning the sheet for duplexing and the like.
After the sheet of support material is separated from the
photoconductive surface of drum 16, the residual toner particles
carried by image and the non-image areas on the photoconductive
surface are removed at cleaning station F. The cleaning station F
includes a blade 74.
It is believed that the foregoing description is sufficient for
purposes of the present application to illustrate the general
operation of an electrophotographic printing machine incorporating
the development apparatus of the present invention therein.
According to the present invention and referring to FIG. 1A,
multi-size photoreceptor flange bearing 100 is shown. Bearing 100
is made of any suitable, durable material such as a metal or a
durable synthetic material, for example a plastic. Preferably, the
bearing is electrically conductive. The bearing also has inherent
lubricating qualities to permit low friction and low wear
operation. For example, the bearing 100 may be made of a bronze,
for example, a powder metal sintered material, i.e. bronze.
Preferably, the bronze bearing 100 is impregnated with a
lubricating material, i.e. carbon. It should be appreciated,
however, that the bearing 100 may be made of an alternate material,
i.e. a plastic impregnated with carbon to provide the lubricating
and electrically conductive properties.
The bearing 100 may have any suitable shape which permits the
rotational motion of the member 16 in the form of for example
photoreceptor drum 16 about axis 102. For example, as shown in FIG.
1A, the bearing 100 has a body 104 which defines a cylindrical
periphery 106 thereof. The bearing body 104 defines a first feature
1 10 as well as a second feature 112.
The bearing 100 supports the member 16 which is typically in the
form of a photoconductive drum. The bearing 100 is connected to the
drum 16 in any suitable fashion. For example, the drum 16 may
include a substrate 114 having a general tubular shape. The
substrate is made of any suitable material and preferably is
electrically conductive, for example, aluminum. The periphery 28 of
the substrate 114 is preferably coated with a photoconductive
material, i.e. selenium or a organic material. The bearing 100 is
connected to the drum 16 in any suitable fashion. For example, hub
116 may be used to connect the drum 16 to the bearing 100. The hub
116 is secured to the photoreceptor drum 16 in any suitable
fashion. For example, as shown in FIG. 1A, the hub 116 includes a
hub large bore 120 to which periphery 28 of the drum 16 is matingly
fitted. It should be appreciated, however, that the hub 116 may
include a stem (not shown) which would matingly fit to drum bore
122 of the substrate 14. The hub 116 is secured to the bearing 100
in any suitable fashion. For example, the hub 116 may include a
small bore 124 which is matingly fitted to periphery 106 of the
bearing 100. To provide for the rotation of the photoconductive
drum 16, the hub 116 may include a gear 130 located on the hub 116.
The gear 130 may include a plurality of teeth 132. The teeth 132
may have any suitable shape and may, for example, be as shown in
FIG. 1A, spur or helical teeth. The gear 130 mates with a driving
gear (not shown) which drives the photoconductive drum 16. The hub
116 is made of any suitable, durable material, for example,
aluminum. It should be appreciated that hub 116 may also be made of
a organic material, i.e. a plastic.
The bearing 100 is operably connected to housing 134. The housing
134 may have any suitable shape for containing the photoconductive
drum 16. As stated earlier the photoconductive drum 16 is a
consumable item and will eventually require replacement. In order
to assist in the placement of the photoconductive drum recently the
photoconductive drum is contained within a module or unit in the
form of a CRU (customer replaceable unit) generally referred to in
FIG. 1A as numeral 136. The housing 134 thus forms part of the CRU
136. When the housing 134 is used as part of a CRU, the housing has
a generally cylindrical shape slightly larger than the drum 16. The
housing 134 may be made of any suitable durable material for
example a plastic in particular a strong plastic perhaps reinforced
with fibers for example nylon or carbon graphite material.
The CRU 136 is removable mounted to a first copy machine 140. The
CRU 136 may be mounted to the machine 140 in any suitable fashion,
for example as shown in FIG. 1A, the machine 140 includes frame 142
from which first support 144 extends. The CRU 136 is thus removably
mounted on support 144.
According to the present invention and referring to FIG. 1B, the
bearing 100 serves to permit the mounting of CRU 136 into the first
machine 140 which has the first support 144 extending from the
frame member 142 (see FIG. 1A) as well as to mount the CRU 136 into
machine 240 which machine 240 includes a second support 244
extending from a second frame member 242. More simply stated, the
bearing 100 accepts both the first support 144 and the second
support 244 permitting the CRU 136 to fit into both machines 140
and 240.
Referring again to FIG. 1A, the bearing 100 includes the first
feature 1 10 which cooperates with the first support 144 to permit
the mounting of the CRU 136 into machine 140. The support 144 and
the first feature 110 may have any suitable shape to permit
cooperation with each other. For example, as shown in FIG. 1A, the
first feature 110 may be in the form of a small bore. The bore 110
may be cylindrical and be defined by diameter D.sub.FF. The first
support 144 may be in the form of a first stem or first shaft and
be cylindrical with a diameter D.sub.FS. The diameter D.sub.FS of
the first shaft 144 is slightly smaller than the diameter D.sub.FF
of the small bore 110 of the bearing 100 to permit insertion
therewith.
The first shaft 144 has a length L.sub.FS which is similar in
length to length L.sub.B of the bearing 100.
Referring now to FIGS. 1 A and 1B, the second feature 112 of the
bearing 100 is in the form of a counterbore having a diameter
D.sub.SF. The small second feature 112 of the bearing 100 is
matingly fitted to the second support 244. The second support 244
may have any suitable size and shape to mate with the second
feature 112 but preferably, according to FIG. 1B, the second
support 244 is in the form of a multi-diameter shaft. The
multi-diameter shaft 244 includes a cylindrical stem 250 which
extends from a cylindrical base 252. The cylindrical stem 250 and
cylindrical base 252 are concentric about axis 254. The cylindrical
base 252 has a diameter D.sub.B which matingly fits into the second
feature 112 of the bearing 100.
The second feature 112 is preferably in the form of a cylindrical
counterbore having a diameter D.sub.SF. Diameter D.sub.B of the
base 252 is slightly smaller than diameter DSF of the second
feature 112 of the bearing 100 to permit cooperation therewith. The
cylindrical stem 250 has a diameter D.sub.S which is similar to
diameter D.sub.FS of the first shaft 144. The cylindrical base 252
has a length L.sub.BA which is similar to length L.sub.SF of the
second feature 112 of the bearing 100. The cylindrical stem 250
extends length LSTfrom the cylindrical base 252 and extends length
Lss from frame member 242. The length L.sub.ST of the cylindrical
stem 250 is roughly equivalent to the length L.sub.FF of the first
feature 110.
The cylindrical stem 250 and the cylindrical base 252 are
concentric with each other to an accurate tolerance of say, for
example, 0.03 mm. Likewise, the counterbore 1 12 and the small bore
110 of the bearing 100 are concentric to each other to a small
tolerance of for example 0.03 mm. The use of a cast sintered metal
bearing 100 inherently provides for the accurate concentricity of
the counterbore 112 to the small bore 110. Likewise, grinding or
other manufacturing techniques can provide for the accurate
concentricity of the cylindrical base 252 to the cylindrical stem
250.
Referring again to FIG. 1A, to assist in the assembly of the CRU
136 onto the support 144, the shaft 144 may include a tapered point
160 which is defined by an included angle of approximately 30 to
150 degrees with 90 degrees being preferable. The bearing 100
likewise includes a lead-in chamfer 162 which defines a chamfer
diameter D.sub.SC slightly larger than D.sub.SF of the bore. The
chamfer 162 is defined further by an included angle II of for
example, 150 to 30 degrees with 90 degrees being preferred. The
transition between the second feature 112 and the first feature 110
preferably includes a lead-in chamfer 164 which assists in the
insertion of the first shaft 144 and the second shaft 244.
Referring again to FIG. 1B, the cylindrical base 252 includes a
lead-in chamfer 260 which is defined by angle Angle has an included
angle of for example 150 to 30 degrees with 90 degrees being
preferred.
Cylindrical stem 250 includes tapered point 262 which is defined by
included angle .SIGMA.. Included angle .SIGMA. may have any
suitable angle of for example 30 to 150 degrees with 90 degrees
being preferred.
Referring now to FIG. 3, the CRU 136 is shown installed into
machine 240. The photoreceptive drum 16 includes the first hub 116
extending from first end 170 of the drum 16 as well as second hub
174 extending from second end 172 of the drum 16. The
photoreceptive drum 16 25 is supported at second end 172 in any
suitable fashion, for example, as shown in FIG. 3, the second hub
174 is fitted into pot 176. It should be appreciated that other
mounting situations, for example, a bearing sleeve fitted into a
shaft as similar to bearing 100 and shaft 244 may be utilized to
support second hub 174.
Referring now to FIG. 4, cartridge replaceable unit 136 is shown
trying to be installed into machine 340. Machine 340 includes shaft
344 which has a diameter DVL which is significantly larger than
diameter DSF Of the bearing 100. It is thus obvious that CRU 136
may not be installed into machine 340. Therefore, the bearing 100
serves to foolproof or prevent the installation of CRU 136 into
machine 340.
Referring now to FIG. 5, CRU 436 is shown installed into machine
440. CRU 436 is very similar to CRU 136 of FIGS. 1 and 4 except
that second hub 474 is different than second hub 174 of FIG. 3 in
that second hub 474 includes bearing 480 which matingly fits with
second end shaft 482. Further, CRU 436 includes shaft 444 which
matingly fits with first feature 410 of bearing 400.
Referring now to FIGS. 6A-6H, alternate support configurations are
shown. CRU 136 as shown in FIGS. 3 and 4 as well as CRU 436 as
shown in FIG. 5 may operate by having the hub rotate around the
bearing or by having the shaft rotate about the bearing.
Preferably, for the CRU 136 the bearing 100 rotates about shaft 144
for the CRU 136, while the bearing 400 rotates about shaft 444 in
CRU 436. When relative rotation may be had between the bearing and
the hub, no rotation between the shaft and the bearing is
necessary. When the shaft and bearing are locked together, the
shaft and bearing configurations as shown in FIGS. 6A-6H are
permissible. As shown in FIGS. 6A-6H, the shaft may include a
portion in the form of a polygon while the bearing may include a
bore which mates with the polygon feature of the shaft.
Referring now to FIGS. 6A and 6B, shaft 544 is shown installed in
bearing 500. Shaft 544 includes rectangular base 552 with a
cylindrical stem 550 extending therefrom. The bearing 500 includes
a cylindrical first feature 510 as well as a rectangular
counterbore 512.
Referring now to FIGS. 6C and 6D, shaft 644 is shown installed in
bearing 600 on machine 640. The shaft 644 includes a cylindrical
stem 650 extending from triangular base 652. The bearing 600
includes a cylindrical bore 610 as well as a triangularly shaped
counterbore 612.
Referring now to FIGS. 6E and 6F, shaft 744 is shown installed in
bearing 700 on machine 740. The shaft 744 includes a cylindrical
stem 750 extending from pentagon shaped base 752. The bearing 700
includes a cylindrical bore 710 as well as a pentagon shaped
counterbore 712.
Referring now to FIGS. 6G and 6H, shaft 844 is shown installed in
bearing 800 on machine 840. The shaft 840 includes a cylindrical
stem 850 extending from hexagonal base 852. The bearing 800
includes a cylindrical bore 810 as well as a hexagon shaped
counterbore 812.
The shafts of FIGS. 6A-6H require a correspondingly matingly shaped
bore to permit the assembly of the shaft into the bearing. This
configuration is very helpful for foolproofing of the proper CRU
into a copy machine. While the configuration shown in FIGS. 6A-6H
require the rotation of the hub about the bearing, it should be
appreciated that by replacing the polygon counterbore within the
bearing with a counterbore within the housing the bearing 100 could
rotate about the cylindrical stem obviating the need for a rotation
between the bearing and the hub.
By providing a multi-size photoreceptor flange bearing, common
photoreceptors can be used with machines having different size
shafts.
By providing a multi-size photoreceptor flange bearing, common
photoreceptors may be utilized reducing the number of different
photoreceptors required for a cartridge replaceable unit
By providing a multi-size photoreceptor flange bearing, common
photoreceptors may be used reducing the number of different
photoreceptors resulting in lower inventory, larger lot sizes,
fewer changeovers, and thereby lower costs for the photoreceptors
and cartridge replaceable units.
By providing a multi-size photoreceptor flange bearing manufactured
from a cast sintered material, common photoreceptors can be used
reducing the number of different photoreceptors with a minimal cost
penalty for the multi-size bushing.
By providing a multi-size photoreceptor flange bearing with
self-lubricating qualities, a CRU may be provided with improved
life.
By providing a multi-size photoreceptor flange bearing having
electrical conductivity, charge transfer can occur through the
bearing of the CRU.
By providing multi-size photoconductive flange bearings,
foolproofing of photoreceptors can be provided to prevent the
installation of an improper photoconductor.
By providing a multi-size photoconductive flange bearings otherwise
identical photoconductive drum can be distinguished by their
stems.
While this invention has been described in conjunction with various
embodiments, it is evident that many alternatives, modifications,
and variations will be apparent to those skilled in the art.
Accordingly, it is intended to embrace all such alternatives,
modifications, and variations as fall within the spirit and broad
scope of the appended claims.
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